Study of the soil macrofauna in tropical cacao-based agroforestry systems in the Dominican Republic

Abstract

Diversified tropical cacao-based agroforestry systems are part of the agroecological movement aiming, inter alia, at creating food systems that do not undermine the ecosystem services. However, the temporal and intra-system practices heterogeneity and their effects on the soil and soil macrofauna as ecosystem services providers still remain unclear. This study aims at exploring relationships between temporal heterogeneity, agricultural practices that generate spatial heterogeneity at plot level, and the soil quality and its macrofauna density and diversity. This study was led in cacao-based diversified AFS in the Dominican Republic. 120 macrofauna samples under leaf litter or cacao pod husks were conducted in 24 plots of 4 age classes. The intra-plot density and diversity was measured and soil analysis were realized. The macrofauna was identified at order level. Statistical analysis were performed to explain the influences of the age of the plantation and the agricultural practices (type of soil cover, tree density and diversity), on the soil chemical and physical parameters, and the macrofauna abundance and diversity. A limited effect of the age of the plantation and no effect of the evolution of tree density and diversity were revealed. Under cacao pods, the macrofauna density and specific richness were higher and the bulk density was lower. Therefore, a managed use of decomposing cacao pods in cacao-based tropical SAF of the Dominican Republic could enhance soil health and secure ecosystem services